1. Field of the Invention
The present invention relates to a video encoding apparatus and method and a video decoding apparatus and method, and more particularly, to a video encoding apparatus and method and a video decoding apparatus and method in which a scalable bitstream supporting at least one coding parameter of at least two bit-depths and at least two video formats with forward compatibility is generated or decoded.
2. Description of the Related Art
In an ordinary video codec according to conventional technology, when the bit-depth of a basic encoder such as a VC-1 encoder, is changed from 8 bits to 10 bits, or when the video format of a basic encoder is simply extended from 4:2:0 to 4:2:2 or 4:4:4, it is impossible for a VC-1 decoder to read and reproduce a bitstream which is generated from improved encoders having the extended bit-depth or the extended video format. Recently, the necessity for development of a video codec which guarantees forward compatibility and then allows a VC-1 decoder and other improved decoders to restore a bitstream encoded with a variety of bit-depths or video formats as well as the fixed bit-depth or fixed video format, has been increasingly highlighted.
That is, since a new video codec which does not guarantee forward compatibility cannot support a terminal having only a conventional basic video codec, reuse of digital content in both terminals having specifications different from each other becomes impossible. In addition, it will take much time for the new video codec to settle into the market, because the new video codec needs to overcome the already established conventional video codec market.